DE 10 2005 033 222 A1 discloses a LUDV valve arrangement in which a control valve forms an inlet metering orifice to which an individual pressure compensator is connected downstream. By the LUDV valve arrangement, a hydraulic consumer connected to two consumer connectors of the control arrangement is triggered. To set a quick traverse, two pressure spaces of the consumer can be connected to one another and to a source of hydraulic fluid. To prevent sagging of the consumer pressure, this connection of the two consumer connectors takes place by the flow path of the hydraulic fluid having a check valve. By the directional control valve, only the connection to one of the consumer connectors is opened. The connection of the other consumer connector to the source of hydraulic fluid and/or the former consumer connector is possible in quick traverse only via the flow path of the hydraulic fluid and the opened check valve. Inadvertent movement of a hydraulic consumer in the quick traverse position of the valve arrangement is prevented with the known solution. The known LUDV control constitutes a special case of load sensing control in which the highest load pressure of the hydraulic consumer is reported to an adjusting pump. The adjustive pump is controlled such that the pump line contains a pump pressure exceeding the load pressure by a certain pressure difference ΔP. In the known LUDV control, the individual pressure compensators are located downstream from the metering orifices and choke the fluid flow between the metering orifice and the load so dramatically that the pressure following all metering orifices is the same, preferably equal to the highest load pressure or slightly above it. The greatest weakness of these hydraulic LS systems is their susceptibility to system vibrations in the load sensing control circuit, among other things due to the load change on the respective consumer.
EP 1 370 773 B1 discloses as a hydraulic valve device a directional control valve for controlling the pressure and the flow of hydraulic oil from and to working connectors of at least one fluid consumer, in which the pressure and flow rate can be controlled by a valve spool moveable in the spool bore and actuatable by at least one drive. By annular channels dynamically connected to the fluid consumer, at a symmetry center point of the valve arrangement, a tank connector annular channel (R) and on either side other annular channels one arranged symmetrically. For implementation of hydraulic pump triggering on one side of the axis of symmetry, with an A-annular channel assigned to one working connector, a first pump pressure annular channel, a first load sensing annular channel and a first end space annular channel are assigned. On the other side of the axis of symmetry, with a B-annular channel assigned to the other working connector, a second pump pressure annular channel, a second load sensing annular channel, and a second end space annular channel are assigned. The first load sensing annular channel is connected to the second load sensing annular channel by a load sensing connecting line. With the known valve solution, a type of quantitative divider for the connected consumers is attained. In these quantitative divider valves, the pressure compensators not controlling the pressure drop over the valve orifice, but accept the highest load pressure of the system. Fluctuating pressure losses in the feed line then directly disrupt the available pressure difference on the controller orifice to hinder constant flow control.